Carbonyl Compounds Introduction
Carbonyl compounds feature a carbon-oxygen double bond. The oxygen's high electronegativity creates a significant dipole, making these compounds polar and highly reactive.
Electronegativity and Polarity
Electronegativity difference between carbon (2.55) and oxygen (3.44) in carbonyls induces polarity. The oxygen atom draws electrons towards itself, creating a partial negative charge.
Polarity Effects on Solubility
Polarity in carbonyl compounds increases solubility in polar solvents like water. This attribute explains the miscibility of many aldehydes and ketones in aqueous media.
Impact on Boiling Points
The polarity of carbonyl groups leads to higher boiling points compared to nonpolar compounds of similar molecular weight, due to stronger dipole-dipole interactions.
Reactivity and Mechanisms
Polar carbonyl compounds are often electrophilic, making them susceptible to nucleophilic attacks. This underpins many organic reactions, including nucleophilic addition and substitution.
Steric Factors and Polarity
Steric hindrance around the carbonyl group can affect the compound's polarity and reactivity. Bulky groups can shield the carbonyl, altering its interaction with solvents and reactants.
Unusual Polar Interactions
In some cases, intramolecular hydrogen bonding can occur with carbonyl compounds, influencing their physical properties and reactivity in unexpected ways.
What feature defines carbonyl compounds?
Carbon-hydrogen single bond
Carbon-oxygen double bond
Oxygen single electron pair
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